xref: /aosp_15_r20/external/webrtc/modules/audio_processing/aec3/vector_math.h (revision d9f758449e529ab9291ac668be2861e7a55c2422)
1 /*
2  *  Copyright (c) 2017 The WebRTC project authors. All Rights Reserved.
3  *
4  *  Use of this source code is governed by a BSD-style license
5  *  that can be found in the LICENSE file in the root of the source
6  *  tree. An additional intellectual property rights grant can be found
7  *  in the file PATENTS.  All contributing project authors may
8  *  be found in the AUTHORS file in the root of the source tree.
9  */
10 
11 #ifndef MODULES_AUDIO_PROCESSING_AEC3_VECTOR_MATH_H_
12 #define MODULES_AUDIO_PROCESSING_AEC3_VECTOR_MATH_H_
13 
14 // Defines WEBRTC_ARCH_X86_FAMILY, used below.
15 #include "rtc_base/system/arch.h"
16 
17 #if defined(WEBRTC_HAS_NEON)
18 #include <arm_neon.h>
19 #endif
20 #if defined(WEBRTC_ARCH_X86_FAMILY)
21 #include <emmintrin.h>
22 #endif
23 #include <math.h>
24 
25 #include <algorithm>
26 #include <array>
27 #include <functional>
28 
29 #include "api/array_view.h"
30 #include "modules/audio_processing/aec3/aec3_common.h"
31 #include "rtc_base/checks.h"
32 
33 namespace webrtc {
34 namespace aec3 {
35 
36 // Provides optimizations for mathematical operations based on vectors.
37 class VectorMath {
38  public:
VectorMath(Aec3Optimization optimization)39   explicit VectorMath(Aec3Optimization optimization)
40       : optimization_(optimization) {}
41 
42   // Elementwise square root.
43   void SqrtAVX2(rtc::ArrayView<float> x);
Sqrt(rtc::ArrayView<float> x)44   void Sqrt(rtc::ArrayView<float> x) {
45     switch (optimization_) {
46 #if defined(WEBRTC_ARCH_X86_FAMILY)
47       case Aec3Optimization::kSse2: {
48         const int x_size = static_cast<int>(x.size());
49         const int vector_limit = x_size >> 2;
50 
51         int j = 0;
52         for (; j < vector_limit * 4; j += 4) {
53           __m128 g = _mm_loadu_ps(&x[j]);
54           g = _mm_sqrt_ps(g);
55           _mm_storeu_ps(&x[j], g);
56         }
57 
58         for (; j < x_size; ++j) {
59           x[j] = sqrtf(x[j]);
60         }
61       } break;
62       case Aec3Optimization::kAvx2:
63         SqrtAVX2(x);
64         break;
65 #endif
66 #if defined(WEBRTC_HAS_NEON)
67       case Aec3Optimization::kNeon: {
68         const int x_size = static_cast<int>(x.size());
69         const int vector_limit = x_size >> 2;
70 
71         int j = 0;
72         for (; j < vector_limit * 4; j += 4) {
73           float32x4_t g = vld1q_f32(&x[j]);
74 #if !defined(WEBRTC_ARCH_ARM64)
75           float32x4_t y = vrsqrteq_f32(g);
76 
77           // Code to handle sqrt(0).
78           // If the input to sqrtf() is zero, a zero will be returned.
79           // If the input to vrsqrteq_f32() is zero, positive infinity is
80           // returned.
81           const uint32x4_t vec_p_inf = vdupq_n_u32(0x7F800000);
82           // check for divide by zero
83           const uint32x4_t div_by_zero =
84               vceqq_u32(vec_p_inf, vreinterpretq_u32_f32(y));
85           // zero out the positive infinity results
86           y = vreinterpretq_f32_u32(
87               vandq_u32(vmvnq_u32(div_by_zero), vreinterpretq_u32_f32(y)));
88           // from arm documentation
89           // The Newton-Raphson iteration:
90           //     y[n+1] = y[n] * (3 - d * (y[n] * y[n])) / 2)
91           // converges to (1/√d) if y0 is the result of VRSQRTE applied to d.
92           //
93           // Note: The precision did not improve after 2 iterations.
94           for (int i = 0; i < 2; i++) {
95             y = vmulq_f32(vrsqrtsq_f32(vmulq_f32(y, y), g), y);
96           }
97           // sqrt(g) = g * 1/sqrt(g)
98           g = vmulq_f32(g, y);
99 #else
100           g = vsqrtq_f32(g);
101 #endif
102           vst1q_f32(&x[j], g);
103         }
104 
105         for (; j < x_size; ++j) {
106           x[j] = sqrtf(x[j]);
107         }
108       }
109 #endif
110       break;
111       default:
112         std::for_each(x.begin(), x.end(), [](float& a) { a = sqrtf(a); });
113     }
114   }
115 
116   // Elementwise vector multiplication z = x * y.
117   void MultiplyAVX2(rtc::ArrayView<const float> x,
118                     rtc::ArrayView<const float> y,
119                     rtc::ArrayView<float> z);
Multiply(rtc::ArrayView<const float> x,rtc::ArrayView<const float> y,rtc::ArrayView<float> z)120   void Multiply(rtc::ArrayView<const float> x,
121                 rtc::ArrayView<const float> y,
122                 rtc::ArrayView<float> z) {
123     RTC_DCHECK_EQ(z.size(), x.size());
124     RTC_DCHECK_EQ(z.size(), y.size());
125     switch (optimization_) {
126 #if defined(WEBRTC_ARCH_X86_FAMILY)
127       case Aec3Optimization::kSse2: {
128         const int x_size = static_cast<int>(x.size());
129         const int vector_limit = x_size >> 2;
130 
131         int j = 0;
132         for (; j < vector_limit * 4; j += 4) {
133           const __m128 x_j = _mm_loadu_ps(&x[j]);
134           const __m128 y_j = _mm_loadu_ps(&y[j]);
135           const __m128 z_j = _mm_mul_ps(x_j, y_j);
136           _mm_storeu_ps(&z[j], z_j);
137         }
138 
139         for (; j < x_size; ++j) {
140           z[j] = x[j] * y[j];
141         }
142       } break;
143       case Aec3Optimization::kAvx2:
144         MultiplyAVX2(x, y, z);
145         break;
146 #endif
147 #if defined(WEBRTC_HAS_NEON)
148       case Aec3Optimization::kNeon: {
149         const int x_size = static_cast<int>(x.size());
150         const int vector_limit = x_size >> 2;
151 
152         int j = 0;
153         for (; j < vector_limit * 4; j += 4) {
154           const float32x4_t x_j = vld1q_f32(&x[j]);
155           const float32x4_t y_j = vld1q_f32(&y[j]);
156           const float32x4_t z_j = vmulq_f32(x_j, y_j);
157           vst1q_f32(&z[j], z_j);
158         }
159 
160         for (; j < x_size; ++j) {
161           z[j] = x[j] * y[j];
162         }
163       } break;
164 #endif
165       default:
166         std::transform(x.begin(), x.end(), y.begin(), z.begin(),
167                        std::multiplies<float>());
168     }
169   }
170 
171   // Elementwise vector accumulation z += x.
172   void AccumulateAVX2(rtc::ArrayView<const float> x, rtc::ArrayView<float> z);
Accumulate(rtc::ArrayView<const float> x,rtc::ArrayView<float> z)173   void Accumulate(rtc::ArrayView<const float> x, rtc::ArrayView<float> z) {
174     RTC_DCHECK_EQ(z.size(), x.size());
175     switch (optimization_) {
176 #if defined(WEBRTC_ARCH_X86_FAMILY)
177       case Aec3Optimization::kSse2: {
178         const int x_size = static_cast<int>(x.size());
179         const int vector_limit = x_size >> 2;
180 
181         int j = 0;
182         for (; j < vector_limit * 4; j += 4) {
183           const __m128 x_j = _mm_loadu_ps(&x[j]);
184           __m128 z_j = _mm_loadu_ps(&z[j]);
185           z_j = _mm_add_ps(x_j, z_j);
186           _mm_storeu_ps(&z[j], z_j);
187         }
188 
189         for (; j < x_size; ++j) {
190           z[j] += x[j];
191         }
192       } break;
193       case Aec3Optimization::kAvx2:
194         AccumulateAVX2(x, z);
195         break;
196 #endif
197 #if defined(WEBRTC_HAS_NEON)
198       case Aec3Optimization::kNeon: {
199         const int x_size = static_cast<int>(x.size());
200         const int vector_limit = x_size >> 2;
201 
202         int j = 0;
203         for (; j < vector_limit * 4; j += 4) {
204           const float32x4_t x_j = vld1q_f32(&x[j]);
205           float32x4_t z_j = vld1q_f32(&z[j]);
206           z_j = vaddq_f32(z_j, x_j);
207           vst1q_f32(&z[j], z_j);
208         }
209 
210         for (; j < x_size; ++j) {
211           z[j] += x[j];
212         }
213       } break;
214 #endif
215       default:
216         std::transform(x.begin(), x.end(), z.begin(), z.begin(),
217                        std::plus<float>());
218     }
219   }
220 
221  private:
222   Aec3Optimization optimization_;
223 };
224 
225 }  // namespace aec3
226 
227 }  // namespace webrtc
228 
229 #endif  // MODULES_AUDIO_PROCESSING_AEC3_VECTOR_MATH_H_
230